Shallow draught vessel



Feb 1969 A. A. OSKOLSKY ETAL 3,426,717v

SHALLOW-DRAUGHT VESSEL Sheet Filed Feb. 28, 1967 Filed Feb. 28, 1967Feb. 11, 1969 AI.A.OSK OLSKY ETAL 1 SHALLOW-DRAUGHT VESSEL Sheetv 2 of 2United States Patent 2 Claims ABSTRACT OF THE DISCLOSURE A small-draughtvessel having a bottom which is concave in the bow section and flat orsubstantially flat in the stern section. The bottom is keel-shapedamidships and turns smoothly into concave lines in the bow section andflat lines in the stern section.

This invention relates to vessels intended for operation inshallow-water basins, where it is necessary to come up directly to theshore.

More particularly, the invention relates to vessels with a combinationsledge-shaped flat-bottomed hull.

There are known shallow-draught vessels whose bottoms are made concavein the bow section (such as the Hickman sea sledge), while the sternsection of their bottom is made hat, or has a somewhat similar form.

However, the use of these vessels in shallow water is hampered owing toair draw-through under the bottom towards the propeller. This rendersthe stable running of the water-jet propeller impossible, or calls forthe installation of the propelling screw deep below the water surface,which is impracticable for sailing in shallow-water basins.

An object of this invention is to eliminate the abovementioneddisadvantages.

A primary object of the invention is the development of ashallow-draught vessel having such lines of the hull which would providefor good hydrodynamic characteristics of the vessel as a whole, forstable functioning of the propeller at the minimum draught, and thepossibility of coming up directly to a non-equipped sloping shore.

The object specified above has been achieved, in accordance with thisinvention, by the development of a vessel whose bottom is made carinateamidships, smoothly turning to concave in the bow section and to fiat inthe stern section.

It is expedient that the bottom of the vessel invented by us would bemade with a general smooth rise towards the bow, as high as thewaterline, said rise extending through a length of not less thanone-third of the vessels overall length, with the purpose of enablingthe vessel to directly contact a sloping shore.

In order that the invention may be readily carried out into effect, anembodiment will now be described by way of an example with reference tothe accompanying diagrammatic drawings in which:

FIGURE 1 is a side view illustrating a vessel in accordance with theinvention.

FIGURE 2 is a plan view of the vessel shown in FIGURE 1.

FIGURE 3 is a section taken on lines I-I of FIG. 1.

FIGURE 4 is a section taken on lines II-II of FIG. 1.

FIGURE 5 is a section taken on lines III-I-II of FIG. 1.

FIGURE 6 is a section taken on lines IV--IV of FIG. 1.

FIGURE 7 is a sheer line drawing of the vessels hull, in accordance withthe invention.

In the bow section the hull of the vessel (FIG. 1) has low-positionedbows 1 forming two bow stems, with a sledge-type vault 2 (FIG. 3)located between said stems.

From the bow section, a gradual transition towards the keel-shaped lines3 of the bottom begins, as shown in FIG. 4.

In the zone of intersection with waterline 4, the lines of the bottomform two vaults 5.

The gradual sinking of the keel line below the line of the bows (FIG. 5)for-ms flat-keeled lines 6 of the vessels bottom.

Further towards the stern (FIG. 6) the vessels lines turn into fiat ones7, or almost flat lines. The shape of the vessels bottom will be moreclearly understood from the sheer line drawing (FIG. 7).

When the vessel covered by this invention sails through the water,low-positioned bows 1 located in the bow section of the hull preventtransverse flow of water from under the hull, thus precluding theformation of the side splash at the stem.

In the zone of waterline intersection with the line of keel, owing tokeel-shaped lines 3 (FIG. 4) of the central section of the bottom,transverse spreading of the onrushing flow of water takes place,resulting in the removal of the air entrapped under the bottom towardsthe bows. Owing to this, stable running (without air indraw) of thewater-jet propeller or shallow-depth propelling screw is ensured. Flatlines 7 (FIG. 6) of the bottom stern section provide for a small draughtof the vessels stern and good hydrodynamic characteristics of the vesselwhen sailing at transitional speeds or when planing.

The vessels shape in plan view (FIG. 2) is close to rectangular whichprovides for the utilization of the bow deck for the accommodation of awheelhouse 8, embarkation platforms 9 and passenger quarters 10.

A high coefiicient of displacement of the hull having theabove-specified lines ensures a small draught of the vessel while atrest, and outstanding hydrodynamic characteristics contributing-to therising of the vessel in the water at transitional speeds and whenplaning.

The lines of the vessel invented by us permit of dispensing with piersand other similar shore facilities, since the vessel is able of directlycontact the bank or shore by the bow, even if the bottom slope at theshore is as small as 3-5.

Moreover, when contacting the shore, the vessel is reliably retainedagainst being swung by the current owing to the stem-shaped bows whichcut into the bottom, thus making any additional mooring superfluous.

The vessels having the lines described herein can be powered bypropellers of various types, including waterjets, propelling screwsinstalled in a tunnel, exposed propelling screws installed at a smalldepth, and others.

-It should be borne in mind that the particular embodiment of theinvention shown in the drawings (FIGS. l-7) is merely one of thepossible and the preferable version of construction, and that there maybe various other versions of embodiment without departing from thespirit and scope of this invention.

What is claimed is:

1. A small-draught vessel whose bottom is made concave in the bowsection, while its stern section has a flat or almost flat shape, andthe bottom is made keel-shaped amidships smoothly turning into concavelines in the bow section, and into fiat lines in the stern section.

2. A small-draught vessel claimed in claim 1, the bottom of said vesselhaving a general gradual rise towards the bow, said rise reaching up tothe waterline and having 4 a length of not less than one-third of thevessel's overall length.

References Cited UNITED STATES PATENTS 2,181,463 11/1939 Pratt 114--56ANDREW H. FARRELL, Primary Examiner.

